(1) Field of the Invention
The present invention relates to an improved deburring nozzle particularly adapted for cleaning and deburring an internal opening. In particular, the present invention relates to an elongated nozzle with an internal restricting orifice that is housed inside of the nozzle, spaced from three lateral slots adjacent to the tip of the nozzle. The restricting orifice extends from a main orifice and increases the velocity of a high pressure working liquid pumped through the main orifice, creating a high velocity, high pressure working liquid that is then moved through the lateral discharge slot(s) in the nozzle. Housing the restricting orifice inside the body of the nozzle greatly increases the working life of the nozzle since the restricting orifice does not become chipped, cracked or worn from coming into contact with the working material. Eliminating such contact significantly lengthens the working life of the nozzle because the discharge slot(s) is not the velocity intensifying member in the nozzle. Thus, even if the discharge slot(s) becomes cracked, chipped or worn, the velocity of the jet exiting the nozzle will not be greatly reduced, due to fanning or spreading out of the jet, because the velocity intensifying restricting orifice remains unaffected by any wear to the discharge slot(s) at the tip of the nozzle. The three discharge slots are preferably positioned symmetrically around a longitudinal axis of the nozzle and provide in excess of 360 degrees of coverage of the jet in a hole in a work material into which the nozzle has been probed.
(2) Prior Art
The use of high velocity liquid jets for penetrating a work surface and for cleaning excess material of construction is well known to the prior art. The prior art nozzles are designed to be mounted in a nozzle assembly or holder. The work material passes in front of the nozzle, with the jet penetrating the work material. The velocity intensifying orifice or the restricting orifice of the prior art nozzles is usually positioned at the tip of the nozzle and functions as the jet exit from the nozzle. The prior art nozzles are not typically subjected to a striking or hitting contact with the work material. There is therefore little risk of damage to the restricting orifice which would significantly diminish the velocity of the jet exiting the restricting orifice at the tip of the nozzle. Illustrative of the prior art nozzles are U.S. Pat. Nos. 4,497,664 to Verry; 3,851,899 to Franz; 3,756,106 to Chadwick et. al; 3,750,961 to Franz; and 3,705,693 to Franz.
High velocity jets have been adapted for use in cleaning or deburring excess material of construction from transmission fluid channels of a transmission main control valve body or like openings. These high velocity jets are produced by a nozzle having an elongate body which produces a jet pattern that almost completely covers the entire radial area around the axis at the tip of the nozzle. In these prior art nozzles, a slot(s) at the tip of the nozzle serves as the restricting orifices and there is a straight internal passage to the slot(s) in the nozzle. Thus, the velocity increase comes from the slot(s) which has a very small dimension, typically 0.010 cm to 0.125 cm. The problem is that the slot(s) is damaged when it contacts the work material. This damage will enlarge the slot(s) and liquid exiting the slot(s). Also, the slot(s) wears out from the fluid motion.